This relates generally to computer systems and, particularly, to firmware used in connection with booting computer systems.
A computer system may boot using firmware including a basic input/output system stored on a memory such as a flash memory. The pre-boot environment is characterized by initiating power to a given platform, and fetching a set of code from the platform firmware to commence boot in the processor.
For an extensible firmware interface (EFI) compliant system, there is firmware in a flash memory that executes and germinates an EFI operational environment. EFI is characterized by a set of boot services, including memory allocation, time, stall, and setting time. In addition, EFI is characterized by a set of protocols that are installable interfaces identified by globally unique identifiers. The various protocol capabilities or services can be published for global use. For example, if the computing device has the universal serial bus, there is a protocol for that bus that a driver publishes. EFI includes a class of images or executables called EFI drivers. An EFI driver is a portable executable, common object file format image. The EFI 1.1 Specification may be obtained from Intel Corporation, Santa Clara, Calif.